With digital image content growing exponentially due to a blossoming of digital photography and the power of the Internet, it becomes an increasing challenge to browse through voluminous image databases. Visually summarizing vacation photos in a home computer directory or images returned from an Internet search query poses a challenge. To make browsing these images more efficient and enjoyable, various conventional image summarization techniques try to address this challenge. Most of these conventional techniques rely on content-based methods such as image clustering and categorization to provide a high-level description of a set of images.
One simple conventional technique for image arrangement is page layout, which aims to maximize page coverage without image overlap. However, both page layout techniques and image mosaic techniques share a similar drawback—they waste display area by showing parts of an image that are not important.
An interactive approach for combining multiple images is interactive digital photomontage. The user manually specifies salient regions of importance or focus on each image and this conventional technique creates a single composite image. The technique works well only when all input images are roughly aligned. But in most practical situations, images are usually considerably different from each other and not aligned.
Digital tapestry is another conventional technique that formulates the selection of salient regions and their placement together as a Markov Random Field (MRF) problem. However, artifacts are introduced along the boundaries of two neighboring salient regions of two different images in the digital tapestry. Although artifact removal methods might be used to correct this flaw, there are still obvious artifacts, which make the final tapestry unnatural or unrealistic.